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Finding the Fourth Proportional to 491.78, 738.11 and 389.36

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Solution

The fourth proportional to 491.78, 738.11 and 389.36 is: 584.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.78 : 738.11 = 389.36 : x
  2. Step 2: Convert to fraction form
    491.78/738.11 = 389.36/x
  3. Step 3: Cross multiply
    491.78x = 738.11 × 389.36
  4. Step 4: Simplify right side
    491.78x = 287,387.79
  5. Step 5: Solve for x
    x = 287,387.79/491.78
  6. Step 6: Final answer
    x = 584.39

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.